Herbicidal substituted thiodiazolyloxyacetamides

ABSTRACT

Herbicidal substituted thiadiazolyloxyacetamides of the formula ##STR1## in which R 1  stands for hydrogen or for an optionally substituted radical from the group consisting of alkyl, alkenyl, alkinyl and aralkyl, 
     R 2  stands for an optionally substituted radical from the group consisting of alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkenyl, aralkyl, aryl, alkoxy, alkenyloxy and alkinyloxy, or 
     R 1  and R 2  together with the nitrogen atom to which they are bonded form an optionally substituted, saturated or unsaturated heterocycle which can contain further hetero atoms and to which a benzo group can be fused, and 
     R 3  stands for an optionally substituted alkyl radical. 
     Intermediates of the formulas ##STR2## in which R 3  stands for optionally substituted alkyl, and 
     X stands for S or SO 2 , 
     are also new.

The invention relates to novel substituted thiadiazolyloxyacetamides, aprocess and novel intermediates or their preparation and their use asherbicides.

It has already been disclosed that certain heteroryloxyacetamides, suchas, for example, N-methyl-2-(benzothiazol-2-yl-oxy)-acetanilide, showherbicidal properties (cf. U.S. Pat. No. 4,509,971). However, theherbicidal activity of the previously known compounds is not alwayscompletely satisfactory.

Novel substituted thiadiazolyloxyacetamides of the general formula (I)##STR3## in which R¹ stands for hydrogen or for an optionallysubstituted radical from the series comprising alkyl, alkenyl, alkinylor aralkyl,

R² stands for an optionally substituted radical from the seriescomprising alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkenyl, aralkyl,aryl, alkoxy, alkenyloxy or alkinyloxy, or

R¹ and R² together with the nitrogen atom to which they are bonded forman optionally substituted, saturated or unsaturated heterocycle whichcan contain further hetero atoms and to which a benzo group can befused, and

R³ stands for an optionally substituted alkyl radical,

have now been found.

Furthermore, it has been found that the novel substitutedthiadiazolyloxyacetamides of the general formula (I) are obtained whenmethylsulphonylthiadiazoles of the general formula (II) ##STR4## inwhich R³ has the abovementioned meaning,

are reacted with hydroxyacetamides of the general formula (II) ##STR5##in which R¹ and R² have the abovementioned meanings, if appropriate inthe presence of a diluent, if appropriate in the presence of anacid-binding agent and if appropriate in the presence of a catalyst.

Finally, it has been found that the novel substitutedthiadiazolyloxyactamides of the general formula (I) possess interestingherbicidal properties. Surprisingly, the novel substitutedthiadiazolyloxyacetamides of the general formula (I) show a considerablymore powerful herbicidal action against common weeds which are difficultto control than the abovementioned compound while having good tolerancetowards important crop plants.

The invention preferably relates to compounds of the formula (I) inwhich

R¹ stands for hydrogen, C₁ -C₈ -alkyl which is optionally substituted byfluorine, chlorine, cyano or C₁ -C₄ -alkoxy, for C₂ -C₈ -alkenyl whichis optionally substituted by fluorine and/or chlorine, for C₂ -C₈-alkinyl or for benzyl,

R² stands for C₁ -C₈ -alkyl which is optionally substituted by fluorine,chlorine, cyano or C₁ -C₄ -alkoxy, for C₂ -C₈ -alkenyl which isoptionally substituted by fluorine and/or chlorine, for C₂ -C₈ -alkinyl,for C₃ -C₆ -cycloalkyl which is optionally substituted by chlorineand/or C₁ -C₃ -alkyl, for C₅ - or C₆ -cycloalkenyl, for benzyl which isoptionally substituted by fluorine, chlorine and/or C₁ -C₄ -alkyl, forphenyl which is optionally substituted by fluorine, chlorine, bromine,iodine, cyano, nitro, C₁ -C₄ -alkyl, trifluoromethyl, C₁ -C₄ -alkoxyand/or C₁ -C₄ -alkylthio, for C₁ -C₈ -alkoxy which is optionallysubstituted by C₁ -C₄ -alkoxy, or for C₃ -C₄ -alkenyloxy, or R¹ and R²together with the nitrogen atom to which they are bonded form asaturated or unsaturated, five- to seven-membered nitrogen heterocyclewhich is optionally monosubstituted to trisubstituted by C₁ -C₃ -alkyland which is optionally benzo-fused, and

R³ stands for C₁ -C₆ -alkyl which is optionally substituted by halogen,C_(1-C) ₄ -alkoxy, C₁ -C₄ -alkylsulphonyl, phenyl, phenoxy or phenyl-C₁-C₄ alkoxy, the phenyl component being optionally substituted byhalogen, C_(1-C) ₄ -alkyl, trifluoromethyl and/or C₁ -C₄ -alkoxy.

The invention particularly relates to compounds of the formula (I) inwhich

R¹ stands for C₁ -C₄ -alkyl, allyl or propargyl,

R² stands for C₁ -C₆ -alkyl, C₁ -C₂ -alkoxy-C₁ -C₂ -alkyl, allyl,propargyl, cyclopentyl, cyclohexyl, cyclohexenyl, benzyl, phenyl (whichis optionally substituted by fluorine, chlorine, bromine, cyano, nitro,methyl, ethyl, trifluoromethyl, methoxy or ethoxy), C_(1-C) ₆ -alkoxy orC₁ -C₂ -alkoxy-C₁ -C₂ -alkoxy, or

R¹ and R² together with the nitrogen atom to which they are bonded standfor piperidinyl which is optionally monosubstituted to trisubstituted bymethyl and/or ethyl, for pyrrolidinyl which is optionallymonosubstituted or disubstituted by methyl and/or ethyl, forperhydroazepinyl or for 1,2,3,4-tetrahydro-quinolinyl, and

R³ stands for methyl, ethyl, propyl, isopropyl, butyl, isobutyl,sec-butyl, tert-butyl, trifluoroethyl, trichloroethyl, methoxyethyl,ethoxyethyl, methylsulphonylethyl, ethylsulphonylethyl, benzyl,chlorobenzyl, phenylethyl or benzyloxyethyl. Examples of the compoundsof the formula (I) are listed in table 1 below.

                                      TABLE 1                                     __________________________________________________________________________     ##STR6##                                 (I)                                 Examples of the compounds of the formula (I)                                   R.sup.3       R.sup.1                                                                               R.sup.2                                                                                  ##STR7##                                    __________________________________________________________________________    CH.sub.3      CH.sub.3                                                                              CH.sub.3                                                CH.sub.3      C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                         CH.sub.3      C.sub.3 H.sub.7                                                                       C.sub.3 H.sub.7                                         CH.sub.3      C.sub.4 H.sub.9                                                                       C.sub.4 H.sub.9                                         CH.sub.3      CH.sub.3                                                                              C.sub.4 H.sub.9                                         CH.sub.3      CH.sub.3                                                                               ##STR8##                                               CH.sub.3      CH.sub.2 CHCH.sub.2                                                                   CH.sub.2 CHCH.sub.2                                     CH.sub.3      CH.sub.2 CCH                                                                          CH.sub.2 CCH                                            CH.sub.3                                                                                     ##STR9##                                                                             OCH.sub.3                                               CH.sub.3      CH(CH.sub.3).sub.2                                                                    OCH(CH.sub.3).sub.2                                     CH.sub.3      CH(CH.sub.3).sub.2                                                                    OCH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                     CH.sub.3      CH.sub.3                                                                              C.sub.5 H.sub.11                                        CH.sub.3      CH.sub.3                                                                              C.sub.6 H.sub.13                                        CH.sub.3      CH.sub.3                                                                               ##STR10##                                              CH.sub.3      CH.sub.3                                                                               ##STR11##                                              CH.sub.3      CH.sub.3                                                                               ##STR12##                                              CH.sub.3      CH.sub.3                                                                               ##STR13##                                              CH.sub.3      CH.sub.3                                                                               ##STR14##                                              CH.sub.3      CH.sub.3                                                                               ##STR15##                                              CH.sub.3      CH.sub.3                                                                               ##STR16##                                              CH.sub.3      CH.sub.3                                                                               ##STR17##                                              CH.sub.3      CH.sub.3                                                                               ##STR18##                                              CH.sub.3      CH.sub.3                                                                               ##STR19##                                              CH.sub.3      CH.sub.3                                                                               ##STR20##                                              CH.sub.3      CH.sub.3                                                                               ##STR21##                                              CH.sub.3      CH.sub.3                                                                               ##STR22##                                              CH.sub.3      CH.sub.3                                                                               ##STR23##                                              CH.sub.3                                                                                                        ##STR24##                                   CH.sub.3                                                                                                        ##STR25##                                   CH.sub.3                                                                                                        ##STR26##                                   CH.sub.3                                                                                                        ##STR27##                                   CH.sub.3                                                                                                        ##STR28##                                   CH.sub.3                                                                                                        ##STR29##                                   CH.sub.3      C.sub.2 H.sub.5                                                                        ##STR30##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR31##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR32##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR33##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR34##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR35##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR36##                                              CH.sub.3      CH(CH.sub.3).sub.2                                                                     ##STR37##                                              CH.sub.3      C.sub.3 H.sub.7                                                                        ##STR38##                                              C.sub.2 H.sub.5                                                                             CH.sub.3                                                                              C.sub.4 H.sub.9                                         C.sub.2 H.sub.5                                                                             C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                         C.sub.2 H.sub.5                                                                             CH(CH.sub.3).sub.2                                                                    CH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                      C.sub.2 H.sub.5                                                                             CH.sub.3                                                                               ##STR39##                                              C.sub.2 H.sub.5                                                                             CH(CH.sub.3).sub.2                                                                     ##STR40##                                              C.sub.3 H.sub.7                                                                             CH.sub.3                                                                               ##STR41##                                              C.sub.3 H.sub.7                                                                             CH(CH.sub.3).sub.2                                                                     ##STR42##                                              C.sub.3 H.sub.7                                                                             C.sub.3 H.sub.7                                                                       C.sub.3 H.sub.7                                         CH(CH.sub.3).sub.2                                                                          C.sub.2 H.sub.5                                                                       C.sub.2 H.sub. 5                                        CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                               ##STR43##                                              CH(CH.sub.3).sub.2                                                                          CH(CH.sub.3).sub.2                                                                     ##STR44##                                              C.sub.4 H.sub.9                                                                             CH.sub.3                                                                               ##STR45##                                              CH.sub.2 CH.sub.2 OCH.sub.3                                                                 CH.sub.3                                                                               ##STR46##                                              CH.sub.2 CH.sub.2 OCH.sub.3                                                                 C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                         CH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                                                          CH.sub.3                                                                               ##STR47##                                               ##STR48##    CH.sub.3                                                                               ##STR49##                                               ##STR50##    CH.sub.3                                                                               ##STR51##                                              CH.sub.2 CF.sub.3                                                                           CH.sub.3                                                                               ##STR52##                                              __________________________________________________________________________

If, for example,2-methylsulphonyl-5-methoxy-difluoromethyl-1,3,4-thiadiazole andhydroxyacetopiperidide are used as starting substances, the course ofthe reaction in the process according to the invention can berepresented by the following equation: ##STR53##

Formula (II) provides a general definition of themethylsulphonylthiadiazoles to be used as starting substances in theprocess according to the invention for the preparation of compounds ofthe formula (I).

In formula (II), R³ preferably, or in particular, has the meaning whichhas already been mentioned above in connection with the description ofthe compounds of the formula (I) according to the invention as beingpreferred, or particularly preferred, respectively, for R³.

Examples of the starting substances of the formula (II) which may bementioned are:

5-methoxy-difluoromethyl-, 5-ethoxydifluoromethyl-,5-propoxydifluoromethyl-, 5-isopropoxydifluoromethyl-,5-butoxydifluoromethyl-, 5-isobutoxydifluoromethyl-,5-sec-butoxydifluoromethyl-, 5-tert-butoxydifluoromethyl-,5-(2,2,2-trifluoroethoxy)-difluoromethyl-,5-(2,2,2-trichloroethoxy)-difluoromethyl-,5-(2-methoxyethoxy)-difluoromethyl-, 5-(2-ethoxyethoxy)-difluoromethyl-,5-(2-methylsulphonylethoxy)-difluoromethyl-,5-(2-ethylsulphonylethoxy)-difluoromethyl-, 5-benzyloxydifluoromethyl-,5-(1-phenylethoxy)-difluoromethyl-, 5-(2-phenylethoxy)-difluoromethyl-,5-(2-chloro-benzyloxy)-difluoromethyl-, 5-(3-chloro-benzyl-oxy)-difluoromethyl-, 5-(4-chloro-benzyloxy)-difluoromethyl- and5-(2-benzyloxy-ethoxy)-difluoromethyl-2-methylsulphonyl-1,3,4-thiadiazole.

The starting substances of the formula (II) were hitherto unknown fromthe literature and also form the subject-matter of the presentinvention.

The novel compounds of the formula (II) are obtained whenmethylthio-thiadiazoles of the general formula (IV) ##STR54## in whichR³ has the abovementioned meaning, are reacted with an oxidizing agent,such as, for example, hydrogen peroxide, if appropriate in the presenceof a catalyst, such as, for example, sodium tungstate, and ifappropriate in the presence of diluents, such as, for example, water,formic acid and/or acetic acid, at temperatures between 0° C. and 100°C.

Formula (IV) provides a general definition of the methylthiothiadiazolesrequired as intermediates. In formula (IV), R³ preferably, or inparticular, has the meaning which has already been mentioned above inconnection with the description of the compounds of the formula (I)according to the invention as being preferred, or particularlypreferred, respectively, for R³.

Examples of the intermediates of the formula (IV) which may be mentionedare:

5-methoxy-difluoromethyl-, 5-ethoxydifluoromethyl-,5-propoxydifluoromethyl-, 5-isopropoxydifluoromethyl-,5-butoxydifluoromethyl-, 5-isobutoxydifluoromethyl-,5-sec-butoxydifluoromethyl-, 5-tert-butoxydifluoromethyl-,5-(2,2,2-trifluoroethoxy)-difluoromethyl-,5-(2,2,2-trichloroethoxy)-difluoromethyl-,5-(2-methoxyethoxy)-difluoromethyl-, 5-(2-ethoxyethoxy)-difluoromethyl-,5-(2-methylsulphonylethoxy)-difluoromethyl-,5-(2-ethylsulphonylethoxy)-difluoromethyl-, 5-benzyloxydifluoromethyl-,5-(1-phenylethoxy)-difluoromethyl-, 5-(2-phenylethoxy)-difluoromethyl-,5-(2-chloro-benzyloxy)-difluoromethyl-,5-(3-chloro-benzyloxy)-difluoromethyl-,5-(4-chloro-benzyloxy)-difluoromethyl- and5-(2-benzyloxy-ethoxy)-difluoromethyl-2-methylthio-1,3,4-thiadiazole.

The intermediates of the formula (IV) were hitherto unknown from theliterature and also form the subject-matter of the present invention.

The novel compounds of the formula (IV) are obtained when5-chlorodifluoromethyl-2-methylthio-1,3,4-thiadiazole of the formula (V)##STR55## is reacted with hydroxy compounds of the general formula (VI)

    R.sup.3 --OH                                               (VI)

in which

R³ has the abovementioned meaning, or with sodium or potassium saltsthereof, if appropriate in the presence of diluents, such as, forexample, acetone, acetonitrile or toluene, at temperatures between 0° C.and 50° C.

5-Chlorodifluoromethyl-2-methylthio-1,3,4-thiadiazole, of the formula(V), was hitherto unknown from the literature and also forms the subjectmatter of the present invention.

The novel compound of the formula (V) is obtained whenchlorodifluoroacetic acid is reacted with methyl dithiocarbazate in thepresence of phosphorus oxychloride and if appropriate in the presence ofan acid acceptor, such as, for example, potassium carbonate, and ifappropriate in the presence of a diluent, such as, for example, toluene,at temperatures between 0° C. and 100° C.

Formula (III) provides a general definition of the hydroxyacetamidesalso to be used as starting substances. In formula (III), R¹ and R²preferably, or in particular, have those meanings which have alreadybeen mentioned above in connection with the description of the compoundsaccording to the invention of the formula (I) as being preferred, orparticularly preferred, respectively, for R¹ or R².

Examples of the starting substances of the formula (III) are listed inTable 2 below.

                                      TABLE 2                                     __________________________________________________________________________    Examples of the starting substances of the formula (III)                       ##STR56##                        (III)                                       R.sup.1 R.sup.2    R.sup.1                                                                              R.sup.2                                             __________________________________________________________________________    CH.sub.3                                                                              OCH(CH.sub.3).sub.2                                                                      CH.sub.3                                                                             OCH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                 CH.sub.3                                                                              CH(CH.sub.3).sub.2                                                                       CH.sub.3                                                                             CH.sub.2 CH(CH.sub.3).sub.2                         CH.sub.3                                                                               ##STR57## C.sub.2 H.sub.5                                                                      OC.sub.2 H.sub.5                                    C.sub.2 H.sub.5                                                                       OCH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                                                      C.sub.2 H.sub.5                                                                      OCH.sub.2 CH(CH.sub.3).sub.2                        CH.sub.3                                                                               ##STR58## CH.sub.3                                                                              ##STR59##                                          CH.sub.3                                                                               ##STR60## CH.sub.3                                                                              ##STR61##                                          CH.sub.3                                                                               ##STR62## CH.sub.3                                                                              ##STR63##                                          CH.sub.3                                                                               ##STR64## CH.sub.3                                                                              ##STR65##                                          CH.sub.3                                                                               ##STR66## CH.sub.3                                                                              ##STR67##                                          CH.sub.3                                                                               ##STR68## C.sub.2 H.sub.5                                                                       ##STR69##                                          CH.sub.3                                                                               ##STR70## CH.sub.3                                                                              ##STR71##                                          CH.sub.3                                                                               ##STR72## CH.sub.3                                                                              ##STR73##                                          CH.sub.3                                                                               ##STR74## CH.sub.3                                                                              ##STR75##                                          CH.sub.3                                                                               ##STR76## CH.sub.3                                                                             CH.sub.3                                            CH(CH.sub.3).sub.2                                                                     ##STR77## C.sub.2 H.sub.5                                                                       ##STR78##                                          C.sub.2 H.sub.5                                                                        ##STR79## C.sub.2 H.sub.5                                                                       ##STR80##                                          CH(CH.sub.3).sub.2                                                                     ##STR81## CH(CH.sub.3).sub.2                                                                    ##STR82##                                          CH(CH.sub.3).sub.2                                                                     ##STR83## CH(CH.sub.3).sub.2                                                                    ##STR84##                                          CH(CH.sub.3).sub.2                                                                     ##STR85## CH(CH.sub.3).sub.2                                                                    ##STR86##                                          C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                          C.sub.3 H.sub.7                                                                      C.sub.3 H.sub.7                                     CH(CH.sub.3).sub.2                                                                    CH(CH.sub.3).sub.2                                                                       CH(CH.sub.3).sub.2                                                                   OCH.sub.3                                           CH(CH.sub.3).sub.2                                                                    OCH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                                                      CH(CH.sub.3).sub.2                                                                   OC.sub.2 H.sub.5                                    CH(CH.sub.3).sub.2                                                                    OC.sub.3 H.sub.7                                                                         CH.sub.3                                                                             OCH.sub.2 CH(CH.sub.3).sub.2                        CH.sub.3                                                                              CH.sub.2 OCH.sub.3                                                                       C.sub.4 H.sub.9                                                                      C.sub.4 H.sub.9                                     C.sub.2 H.sub.5                                                                       OCH.sub.3  CH.sub.3                                                                             CH.sub.2 CF.sub.3                                   CH.sub.2 CHCH.sub.2                                                                   CH.sub. 2 CHCH.sub.2                                                                     CH.sub.2 CCH                                                                         CH.sub.2 CCH                                        CH.sub.3                                                                              CH.sub.2 CCH                                                                              ##STR87##                                                                           OCH.sub.3                                            ##STR88##                                                                            OCH.sub.3  CH.sub.3                                                                              ##STR89##                                          C.sub.2 H.sub.5                                                                        ##STR90## CH(CH.sub.3).sub.2                                                                    ##STR91##                                          C.sub.2 H.sub.5                                                                       CH.sub.2 CCH                                                                             CH(CH.sub.3).sub.2                                                                   CH.sub.2 CCH                                        CH(CH.sub.3).sub.2                                                                    OCH(CH.sub.3).sub.2                                                   __________________________________________________________________________     ##STR92##                                                                                   ##STR93##                                                      __________________________________________________________________________     ##STR94##                                                                                   ##STR95##                                                       ##STR96##                                                                                   ##STR97##                                                       ##STR98##                                                                                   ##STR99##                                                                     ##STR100##                                                      ##STR101##                                                                                  ##STR102##                                                     __________________________________________________________________________

The hydroxyacetamides of the formula (III) are known and/or can beprepared by processes known per se (cf. U.S. Pat. Nos. 4,509,971 and4,645,525; furthermore U.S. Pat. No. 4,334,073, DE-A 3,038,598, DE-A3,038,636 and EP-A 37,526).

The process according to the invention for the preparation of the novelsubstituted thiadiazolyloxyacetamides of the formula (I) is preferablycarried out using diluents. These preferably include hydrocarbons, suchas, for example, toluene, xylene or cyclohexane, halogenohydrocarbons,such as, for example, methylene chloride, ethylene chloride, chloroformor chlorobenzene, ethers, such as, for example, diethyl ether, dipropylether, diisopropyl ether, dibutyl ether, diisobutyl ether, glycoldimethyl ether, tetrahydrofuran and dioxane, alcohols, such as, forexample, methanol, ethanol, propanol, isopropanol or butanol, ketones,such as, for example, acetone, methyl ethyl ketone, methyl isopropylketone and methyl isobutyl ketone, esters, such as, for example, methylacetate and ethyl acetate, amides, such as, for example,dimethylformamide, dimethylacetamide and N-methyl-pyrrolidone, nitriles,such as, for example, acetonitrile and propionitrile, sulphoxides, suchas, for example, dimethyl sulphoxide, and also water or aqueous saltsolutions.

Salts which can preferably be used are chlorides or sulphates of alkalimetals or alkaline earth metals, such as, for example, sodium chloride,potassium chloride or calcium chloride. Sodium chloride is particularlypreferred.

The process according to the invention is advantageously carried outusing acid-binding agents. Acid-binding agents which are preferably usedare strongly basic alkali metal compounds and alkaline earth metalcompounds, for example oxides, such as, for example, sodium oxide,potassium oxide, magnesium oxide and calcium oxide, hydroxides, such as,for example, sodium hydroxide, potassium hydroxide, magnesium hydroxideand calcium hydroxide and/or carbonates, such as, for example, sodiumcarbonate, potassium carbonate, magnesium carbonate and calciumcarbonate.

The addition of 0.01 to 10% by weight (based on glycolamide employed, ofthe formula (III)) of a phase transfer catalyst may prove advantageousin some cases. Examples of such catalysts which may be mentioned are:tetrabutylammonium chloride, tetrabutylammonium bromide,tributyl-methylphosphonium bromide, trimethyl-C₁₃ /C₁₅ -alkyl-ammoniumchloride, dibenzyl-dimethyl-ammonium methylsulphate, dimethyl-C₁₂ /C₁₄-alkyl-benzylammonium chloride, tetrabutylammonium hydroxide,18-crown-6, triethylbenzylammonium chloride, trimethylbenzylammoniumchloride, tetraethylammonium bromide.

In the process according to the invention, the reaction temperatures canbe varied within a relatively wide range. In general, the process iscarried out at temperatures between -50° C. and +110° C., preferably attemperatures between -20° C. and +100° C.

In general, the process according to the invention is carried out underatmospheric pressure, but it can can also be carried out at increased orreduced pressure, e.g. between 0.1 and 10 bar.

For carrying out the process according to the invention, 0.5 to 5 moles,preferably 0.8 to 1.5 moles, of hydroxyacetamide of the formula (III)are generally employed per mole of methylsulphonylthiadiazole of theformula (II). The reactants can be combined in any desired sequence. Thereaction mixture is in each case stirred until the reaction is complete,and the work-up is carried out by customary methods.

The active compounds according to the invention can be used asdefoliants, desiccants, agents for destroying broad-leaved plants and,especially, as weed-killers. By weeds, in the broadest sense, there areto be understood all plants which grow in locations where they areundesired. Whether the substances according to the invention act astotal or selective herbicides depends essentially on the amount used.

The active compounds according to the invention can be used, forexample, in connection with the following plants:

Dicotyledon weeds of the genera: Sinapis, Lepidium, Galium, Stellaria,Matricaria, Anthemis, Galinsoga, Chenopodium, Urtica, Senecio,Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum,Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa, Rotala,Lindernia, Lamium, Veronica, Abutilon, Emex, Datura, Viola, Galeopsis,Papaver and Centaurea.

Dicotyledon cultures of the genera: Gossypium, Glycine, Beta, Daucus,Phaseolus, Pisum, Solanum, Linum, Ipomoea, Vicia, Nicotiana,Lycopersicon, Arachis, Brassica, Lactuca, Cucumis and Cucurbita.

Monocotyledon weeds of the genera: Echinochloa, Setaria, Panicum,Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus,Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis,Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea,Dactyloctenium, Agrostis, Alopecurus and Apera.

Monocotyledon cultures of the genera: Oryza, Zea, Triticum, Hordeum,Avena, Secale, Sorghum, Panicum, Saccharum, Ananas, Asparagus andAllium.

However, the use of the active compounds according to the invention isin no way restricted to these genera, but also extends in the samemanner to other plants.

The compounds are suitable, depending on the concentration, for thetotal combating of weeds, for example on industrial terrain and railtracks, and on paths and squares with or without tree plantings.Equally, the compounds can be employed for combating weeds in perennialcultures, for example afforestations, decorative tree plantings,orchards, vineyards, citrus groves, nut orchards, banana plantations,coffee plantations, tea plantations, rubber plantations, oil palmplantations, cocoa plantations, soft fruit plantings and hopfields, andfor the selective combating of weeds in annual cultures.

The compounds of the formula (I) according to the invention areparticularly suitable for selectively combating monocotyledon weeds inmonocotyledon and dicotyledon crops, especially using the pre-emergencemethod.

The active compounds can be converted to the customary formulations,such as solutions, emulsions, wettable powders, suspensions, powders,dusting agents, pastes, soluble powders, granules, suspension-emulsionconcentrates, natural and synthetic materials impregnated with activecompound, and very fine capsules in polymeric substances.

These formulations are produced in a known manner, for example by mixingthe active compounds with extenders, that is liquid solvents and/orsolid carriers, optionally with the use of surface-active agents, thatis emulsifying agents and/or dispersing agents and/or foam-formingagents.

In the case of the use of water as an extender, organic solvents can,for example, also be used as auxiliary solvents. As liquid solvents,there are suitable in the main: aromatics, such as xylene, toluene oralkylnaphthalenes, chlorinated aromatics and chlorinated aliphatichydrocarbons, such as chlorobenzenes, chloroethylenes or methylenechloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, forexample petroleum fractions, mineral and vegetable oils, alcohols, suchas butanol or glycol as well as their ethers and esters, ketones, suchas acetone, methyl ethyl ketone, methyl isobutyl ketone orcyclohexanone, strongly polar solvents, such as dimethylformamide anddimethyl sulphoxide, as well as water.

As solid carriers there are suitable: for example ammonium salts andground natural minerals, such as kaolins, clays, talc, chalk, quartz,attapulgite, montmorillonite or diatomaceous earth, and ground syntheticminerals, such as highly disperse silicic acid, alumina and silicates,as solid carriers for granules there are suitable: for example crushedand fractionated natural rocks such as calcite, marble, pumice,sepiolite and dolomite, as well as synthetic granules of inorganic andorganic meals, and granules of organic material such as sawdust, coconutshells, corn cobs and tobacco stalks; as emulsifying and/or foam-formingagents there are suitable: for example non-ionic and anionicemulsifiers, such as polyoxyethylene-fatty acid esters,polyoxyethylene-fatty alcohol ethers, for example alkylaryl polyglycolethers, alkylsulphonates, alkyl sulphates, arylsulphonates as well asalbumin hydrolysis products; as dispersing agents there are suitable:for example lignin-sulphite waste liquors and methylcellulose.

Adhesives such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latices, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, as well as naturalphospholipids, such as cephalins and lecithins, and syntheticphospholipids, can be used in the formulations. Further additives can bemineral and vegetable oils.

It is possible to use colorants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyestuffs,such as alizarin dyestuffs, azo dyestuffs and metal phthalocyaninedyestuffs, and trace nutrients such as salts of iron, manganese, boron,copper, cobalt, molybdenum and zinc.

The formulations in general contain between 0.1 and 95 percent by weightof active compound, preferably between 0.5 and 90%.

The active compounds according to the invention, as such or in the formof their formulations, can also be used, for combating weeds, asmixtures with known herbicides, finished formulations or tank mixesbeing possible.

Suitable components for the mixtures are known herbicides, such as, forexample,1-amino-6-ethylthio-3(2,2-dimethylpropyl)-1,3,5-triazine-2,4(1H,3H)-dione(AMETHYDIONE) or N-(2-benzothiazolyl)-N,N'-dimethyl-urea(METABENZTHIAZURON) for combating weeds in cereals;4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one (METAMITRON) forcombating weeds in sugar beets and4-amino-6-(1,1-dimethyl-ethyl)-3-methylthio-1,2,4-triazin-5(4H)-one(METRIBUZIN) for combating weeds in soy beans; furthermore alsoN-(methoxymethyl)-2,6-diethyl-chloroacetanilide (ALACHLOR);2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine (ATRAZIN); methyl2-[[[[[(4,6-dimethoxypyrimidin-2-yl)-amino]-carbonyl]-amino]-sulphonyl]-methyl]-benzoate(BENSULFURON); N-(butoxymethyl)-2-chloro-N-(2,6-diethylphenyl)-acetamide(BUTACHLOR); 5-amino-4-chloro-2-phenyl-2,3-dihydro-3-oxy-pyridazine(CHLORIDAZON); ethyl2-{[(4-chloro-6-methoxy-2-pyrimidinyl)-aminocarbonyl]-aminosulphonyl}-benzoate(CHLORIMURON);2-chloro-N-{[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-amino]-carbonyl}-benzenesulphonamide(CHLORSULFURON);exo-1-methyl-4-(1-methylethyl)-2-(2-methylphenyl-methoxy)-7-oxabicyclo-(2,2,1)heptane(CINMETHYLIN); 2-chloro-4-ethylamino-6-(3-cyanopropylamino)-1,3,5-triazine (CYANAZINE); N,S-diethylN-cyclohexyl-thiolcarbamate (CYCLOATE);2-[(2-chlorophenyl)methyl]-4,4-dimethylisoxazolidin-3-one (DIMETHAZONE);S-ethyl N,N-di-n-propyl-thiocarbamate (EPTAME);4-amino-6-t-butyl-3-ethylthio-1,2,4-triazin-5(4H)-one (ETHIOZIN);N,N-dimethyl-N'-(3-trifluoromethylphenyl)-urea (FLUOMETURON);1-methyl-3-phenyl-5-(3-trifluoromethylphenyl)-4-pyridone (FLURIDONE);methyl2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-4(5)-methylbenzoate(IMAZAMETHABENZ);2-[5-methyl-5-(1-methylethyl)-4-oxo-2-imidazolin-2-yl]-3-quinolinecarboxylicacid (IMAZAQUIN);2-[4,5-dihydro-4-methyl-4-isopropyl-5-oxo-(1H)-imidazol-2-yl]-2-(1,3-benzothiazol-2-yloxy)-acetanilide(MEFENACET);2-chloro-N-(2,6-dimethylphenyl)-N-[(1H)-pyrazol-1-yl-methyl]acetamide(METAZACHLOR);2-ethyl-6-methyl-N-(1-methyl-2-methoxyethyl)-chloroacetanilide(METOLACHLOR); S-ethyl N,N-hexamethylenethiolcarbamate (MOLINATE);4-(di-n-propylamino)-3,5-dinitrobenzenesulphonamide (ORYZALIN);N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitroaniline (PENDIMETHALIN)o-chloro-2',6'-diethyl-N-(2-propoxyethyl)-acetanilide (PRETILACHLOR);2,4-bis-[N-ethylamino]-6-methylthio-1,3,5-triazine (SIMETRYNE);4-ethylamino-2-t-butylamino-6-methylthio-s-triazine (TERBUTRYNE); methyl3-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-amino]-carbonyl]-amino]-sulphonyl]-thiophene-2-carboxylate(THIAMETURON); S-2,3,3-trichloroallyl N,N-diisopropylthiolcarbamate(TRIALLATE) and 2,6-dinitro-4-trifluoromethyl-N,N-dipropylaniline(TRIFLURALIN). Surprisingly, some mixtures also show synergistic action.

Mixtures with other known active compounds, such as fungicides,insecticides, acaricides, nematicides, bird repellents, plant nutrientsand agents which improve soil structure, are also possible.

The active compounds can be used as such, in the form of theirformulations or in the use forms prepared therefrom by further dilution,such as ready-to-use solutions, suspensions, emulsions, powders, pastesand granules. They are used in the customary manner, for example bywatering, spraying, atomizing or scattering.

The active compounds according to the invention can be applied eitherbefore or after emergence of the plants.

They can also be incorporated into the soil before sowing.

The amount of active compound used can vary within a substantial range.It depends essentially on the nature of the desired effect. In general,the amounts used are between 0.01 and 10 kg of active compound perhectare of soil surface, preferably between 0.05 and 5 kg per ha.

The preparation and use of the active compounds according to theinvention can be seen from the following examples.

PREPARATION EXAMPLES EXAMPLE 1 ##STR103##

A solution of 0.88 g (0.022 mol) of sodium hydroxide in 4 ml of water isadded dropwise to a stirred mixture of 4.0 g (0.0189 mol) of5-methoxydifluoromethyl-2-methyl-sulphonyl-1,3,4-thiadiazole, 3.1 g(0.0189 mol) of N-methyl-hydroxyacetanilide and 40 ml of acetone, whichhad been cooled to -20° C. The reaction mixture is stirred for 12 hourswith cooling using ice/common salt. The mixture is then acidified usingacetic acid and concentrated under a waterpump vacuum. The residue isshaken with water/toluene, and the organic phase is washed with water,dried using sodium sulphate and filtered. The solvent is carefullyremoved from the filtrate by distillation under a waterpump vacuum.

5.8 g (93% of theory) ofN-methyl-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetanilideare obtained as an oily residue of refractive index n²⁰ =1.5350.

The compounds of the formula (I) listed in table 3 below can also beprepared analoguously to Example I and following the generalinstructions of the preparation process according to the invention:

                  TABLE 3                                                         ______________________________________                                        Preparation Examples of the compounds of the formula (I)                       ##STR104##                    (I)                                            Ex-         R.sup.1      R.sup.2    Physical                                   No.pleam-                                                                          R.sup.3                                                                              ##STR105##            melting point)(m.p. =data                  ______________________________________                                        2    CH.sub.3                                                                             CH(CH.sub.3).sub.2                                                                          ##STR106##                                                                              m.p.: 51° C.                       3    CH.sub.3                                                                             CH(CH.sub.3).sub.2                                                                          ##STR107##                                                                              m.p.: 83° C.                       4    CH.sub.3                                                                             CH(CH.sub.3).sub.2                                                                         OCH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                                                      n.sub.D.sup.20 : 1.4640                   5    CH.sub.3                                                                             CH.sub.3                                                                                    ##STR108##                                                                              n.sub.D.sup.20 : 1.4980                   6    CH.sub.3                                                                             CH.sub.3                                                                                    ##STR109##                                                                              n.sub.D.sup.20 : 1.4930                   7    CH.sub.3                                                                              ##STR110##             n.sub.D.sup.20 : 1.4895                   8    CH.sub.3                                                                             CH.sub.3     C.sub.4 H.sub.9                                                                          n.sub.D.sup.20 : 1.4750                   9    CH.sub.3                                                                              ##STR111##             n.sub.D.sup.20 : 1.4930                   10   CH.sub.3                                                                             CH.sub.2 CHCH.sub.2                                                                        CH.sub.2 CHCH.sub.2                                                                      n.sub.D.sup.20 : 1.4860                   11   CH.sub.3                                                                             CH(CH.sub.3).sub.2                                                                          ##STR112##                                                                              n.sub.D.sup.20 : 1.5289                   12   CH.sub.3                                                                             CH(CH.sub.3).sub.2                                                                          ##STR113##                                                                              m.p.: 108° C.                      13   CH.sub.3                                                                             C.sub.3 H.sub.7                                                                            C.sub.3 H.sub.7                                                                          n.sub.D.sup.20 : 1.4745                   14   CH.sub.3                                                                             CH.sub.3                                                                                    ##STR114##                                                                              m.p.: 96° C.                       15   CH.sub.3                                                                             CH.sub.3     CH.sub.2 C CH                                                                            n.sub.D.sup.20 : 1.4923                   ______________________________________                                    

STARTING SUBSTANCES OF THE FORMULA (II) EXAMPLE (II-1) ##STR115##

200 ml of 35% strength aqueous hydrogen peroxide solution are addeddropwise to a stirred mixture of 40 g (0.16 mol)5-methoxydifluoromethyl-2-methylthio-1,3,4-thiadiazole, 0.2 g of sodiumtungstate and 140 ml of formic acid, which had been warmed to 50° C.,during which process the temperature climbs to 95° C. for a shortperiod. The reaction mixture is then cooled to 0° C., and the productwhich is obtained in the form of crystals is isolated by filtering offwith suction.

22 g (56% of theory) of5-methoxydifluoromethyl-2-methylsulphonyl-1,3,4-thiadiazole of meltingpoint 45° C. are obtained.

STARTING SUBSTANCES OF THE FORMULA (IV) EXAMPLE (IV-1) ##STR116##

A solution of 61 g (1.13 mol) of sodium methoxide in 500 ml of methanolis added dropwise to a stirred solution of 245 g (0.9 mol) of5-chlorodifluoromethyl-2-methylthio-1,3,4-thiadiazole in 600 ml ofmethanol, which had been cooled to 0° C. to 5° C. The reaction mixtureis stirred for 12 hours at 20° C., and then poured into 2 l of water andshaken with 2 l of toluene. The organic phase is separated off, driedusing sodium sulphate and filtered. The filtrate is concentrated under awaterpump vacuum and the residue is distilled under high vacuum.

95 g (50% of theory) of5-methoxy-difluoromethyl-2-methylthio-1,3,4-thiadiazole are obtained asa colorless oil of boiling point 68° C./0.01 mbar.

STARTING COMPOUND OF THE FORMULA (V) ##STR117##

130 g (1.0 mol) of chlorodifluoroacetic acid are added dropwise at 20°C. to a solution of 69 g (0.5 mol) of potassium carbonate in 100 ml ofwater. After the addition of 1.5 l of toluene, the water is removed in awater separator. 121 g (1.0 mol) of methyl dithiocarbazate are added atapprox. 25° C. to the remaining suspension with external cooling, andthen 195 g (1.25 mol) of phosphorus oxychloride are added dropwise at50° C. to 60° C. with this temperature being maintained. The reactionmixture is stirred for two hours and then poured into ice water, and theorganic phase is separated off, washed with water, dried using sodiumsulphate and filtered. The solvent is carefully removed from thefiltrate by distillation under a waterpump vacuum.

190 g (88% of theory) of5-chloro-difluoromethyl-2-methylthio-1,3,4-thiadiazole are obtained asan oily residue which can be purified by distillation under high vacuum.B.p.: 90° C.-95° C./1 mbar.

Use Example

In the following Use Example, the compound of the formula below is usedas comparison substance: ##STR118##N-methyl-2-(benzothiazol-2-yl-oxy)-acetanilide (disclosed in U.S. Pat.No. 4,509,971).

EXAMPLE

Pre-emergence test

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

Seeds of the test plants are sown in normal soil and, after 24 hours,watered with the preparation of the active compound. It is expedient tokeep constant the amount of water per unit area. The concentration ofthe active compound in the preparation is of no importance, only theamount of active compound applied per unit area being decisive. Afterthree weeks, the degree of damage to the plants is rated in % damage incomparison to the development of the untreated control. The figuresdenote:

0%=no action (like untreated control)

100%=total destruction

In this test, for example the compounds according to PreparationExamples (1), (3), (4), (5), (6), (7), (9), (10), (11), (13) and (14)show a clearly superior activity compared with the prior art.

It is understood that the specification and examples are illustrativebut not limitative of the present invention and that other embodimentswithin the spirit and scope of the invention will suggest themselves tothose skilled in the art.

I claim:
 1. A substituted thiadiazolyloxyacetamide of the formula##STR119## in which R¹ stands for hydrogen, C₁ -C₈ -alkyl which isoptionally substituted by fluorine, chlorine, cyano or C₁ -C₄ -alkoxy,for C₂ -C₈ -alkenyl which is optionally substituted by fluorine and/orchlorine, for C₂ -C₈ -alkinyl or for benzyl,R² stands for C₁ -C₈ -alkylwhich is optionally substituted by fluorine, chlorine, cyano or C₁ -C₄-alkoxy, for C₂ -C₈ -alkenyl which is optionally substituted by fluorineand/or chlorine, for C₂ -C₈ alkinyl, for C₃ -C₆ -cycloalkyl which isoptionally substituted by chlorine and/or C₁ -C₃ -alkyl, for C₅ - or C₆-cycloalkenyl, for benzyl which is optionally substituted by fluorine,chlorine and/or C₁ -C₄ -alkyl, for phenyl which is optionallysubstituted by fluorine, chlorine, bromine, iodine, cyano, nitro, C₁ -C₄-alkyl, trifluoromethyl, C₁ -C₄ -alkoxy and/or C₁ -C₄ -alkylthio, for C₁-C₈ -alkoxy which is optionally substituted by C₁ -C₄ -alkoxy, or for C₃-C₄ -alkenyloxy, or R¹ and R² together with the nitrogen atom to whichthey are bonded form a saturated or unsaturated, five- to seven-memberednitrogen heterocycle which is optionally monosubstituted totrisubstituted by C₁ -C₃ -alkyl and which is optionally benzo-fused, andR³ stands for C₁ -C₆ -alkyl which is optionally substituted by halogen,C₁ -C₄ -alkoxy, C₁ -C₄ -alkylsulphonyl, phenyl, phenoxy or phenyl-C₁ -C₄-alkoxy, the phenyl component being optionally substituted by halogen,C₁ -C₄ -alkyl, trifluoromethyl and/or C₁ -C₄ -alkoxy.
 2. A compoundaccording to claim 1, in whichR¹ stands for C₁ -C₄ -alkyl, allyl orpropargyl, R² stands for C₁ -C₆ -alkyl, C₁ -C₂ -alkoxy-C₁ -C₂ -alkyl,allyl, propargyl, cyclopentyl, cyclohexyl, cyclohexenyl, benzyl, phenyl(which is optionally substituted by fluorine, chlorine, bromine, cyano,nitro, methyl, ethyl, trifluoromethyl, methoxy or ethoxy), C₁ -C₂-alkoxy-C₁ -C₂ -alkoxy, or R¹ and R² together with the nitrogen atom towhich they are bonded stand for piperidinyl which is optionallymonosubstituted to trisubstituted by methyl and/or ethyl, forpyrrolidinyl which is optionally monosubstituted or disubstituted bymethyl and/or ethyl, for perhydroazepinyl or for1,2,3,4-tetrahydro-quinolinyl, and R³ stands for methyl, ethyl, propyl,isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, trifluoroethyl,trichloroethyl, methoxyethyl, ethoxyethyl, methylsulphonylethyl,ethylsulphonylethyl, benzyl, chlorobenzyl, phenylethyl orbenzyloxyethyl.
 3. A compound according to claim 1, wherein suchcompound isN-methyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetanilideof the formula ##STR120##
 4. A compound according to claim l, whereinsuch compound isN-isopropyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetanilideof the formula ##STR121##
 5. A compound according to claim 1, whereinsuch compound isN-isopropyl-N-ethoxyethoxy-(5-methoxy-difluoro-3,4-thiadiazol-2-yl)-oxyacetamideof the formula ##STR122##
 6. A compound according to claim 1, whereinsuch compound isN-methyl-N-(3-trifluoromethylphenyl)-(5-methoxydifluoro-methyl-1,3,4-thiadiazol-2-yl)oxyacetamideof the formula ##STR123##
 7. A compound according to claim 1, whereinsuch compound isN-methyl-N-(1-cyclohexenyl)-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetamideof the formula ##STR124##
 8. A compound according to claim 1, whereinsuch compound is(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-yl)-oxyacetic acid2-ethyl-piperidide of the formula ##STR125##
 9. A compound according toclaim 1, wherein such compound is(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-yl)-oxyacetic acidhexamethylenimide of the formula ##STR126##
 10. A compound according toclaim 1, wherein such compound isN,N-diallyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetamideof the formula ##STR127##
 11. A compound according to claim 1, whereinsuch compound isN-isopropyl-N-(3-chlorophenyl)-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetamideof the formula ##STR128##
 12. A compound according to claim 1, whereinsuch compound isN,N-di-propyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetamideof the formula ##STR129##
 13. A compound according to claim 1, whereinsuch compound isN-methyl-N-(2,3-dimethylphenyl)-(5-methoxydifluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetamideof the formula ##STR130##
 14. A herbicidal composition comprising aherbicidally effective amount of a compound according to claim 1 and adiluent.
 15. A method of combating unwanted vegetation which comprisesapplying to such vegetation or to a locus from which it is desired toexclude such vegetation a herbicidally effective amount of a compoundaccording to claim
 1. 16. The method according to claim 15, wherein suchcompoundisN-methyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetanilide,N-isopropyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetanilide,N-isopropyl-N-ethoxyethoxy-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetamide,N-methyl-N-(3-trifluoromethylphenyl)-(5-methoxydifluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetamide,N-methyl-N-(1-cyclohexenyl)-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetamide,(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetic acid2-ethyl-piperidide,(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetic acidhexamethylenimide,N,N-diallyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetamide,N-isopropyl-N-(3-chlorophenyl)-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetamide,N,N-di-propyl-(5-methoxy-difluoro-methyl-1,3,4-thiadiazol-2-yl)-oxyacetamideorN-methyl-N-(2,3-dimethylphenyl)-(5-methoxy-difluoromethyl-1,3,4-thiadiazol-2-yl)-oxyacetamide.